Measuring effective attenuation coefficients of 3D printing materials for anthropomorphic breast phantoms

Anthropomorphic breast phantoms are necessary for image quality evaluation of breast x-ray- systems in realistic conditions. 3D-printing techniques are an alternative for producing breast phantoms. This work aims to experimentally determine the effective x-ray attenuation coefficient (μeff) of 3D-printing materials (PLA, ABS and HIPS), well-known breast tissue-equivalent materials (CIRS Gland and CIRS Fat) and PMMA using a clinical breast x-ray imaging system. Three target-filter combinations were considered: W/Rh 29kVp, W/Ag 30kVp and W/Al 29kVp. To validate the experimental method, effective attenuation coefficients values were obtained with numerical methods and Monte-Carlo simulations. Experimental and numerical μeff relative differences were < 10% for W/Rh and W/Ag acquisition and around 40% for W/Al, because of the scattering radiation. Experimental and MC simulated μeff relative differences were < 14% for W/Rh and W/Ag acquisition and around 2% for W/Al. The relative differences between the effective attenuation coefficients values of PLA and CIRS Gland, and ABS and CIRS Fat were found to be between 2 and 8 %. In consequence, these materials are adequate candidates materials to mimic breast glandular and adipose tissue in anthropomorphic phantoms manufacturing.